Journal for the History of Astronomy

George Airy, the Astronomer Royal between 1835 and 1881, was the most prolific public scientist and governmental adviser in nineteenth-century Britain. His contributions to parliamentary commissions, like his management of the Royal Observatory in Greenwich, have been characterised as an attempt to impose order across Victorian society. However, the cultural subtext to this governmental work has not been explored. By profiling his non-professional investigations into ancient history and scriptural criticism, recorded in the Royal Observatory archives, this article examines the ideas and beliefs that framed Airy’s contribution to Victorian governance. In doing so, it reveals intimate connections between science, administration and cultural heritage in Victorian Britain.

The article discusses the construction, function, and origin of the solar dial in the Olsztyn Castle, traditionally attributed to Copernicus. The dial, preserved partially on the wall of the cloister and presumably designed to determine the time of equinoxes, served as an astronomical instrument mapping the daily paths of the sun in the sky. The article provides a comprehensive mathematical model of the instrument, taking into account the astronomical and architectural factors which affected its functioning. The analysis allows to alienate the essential properties of the dial as an observational instrument and to contend that measurements were recorded indelibly on the wall and averaged by interpolation. Furthermore, it reconsiders the arguments which support the hypothesis ascribing the construction of the Olsztyn instrument to Copernicus. (Some mathematical appendices appear only in the online issue of the journal.)

In his Almagest, Ptolemy provides an astronomical proof to establish the Earth’s centrality. In this paper, I offer a complete survey of this proof, present the main features of Copernican and Galilean heliocentric responses, and elucidate the meaning of some concepts involved in it. I argue that historical analysis allows us to state that the success of Ptolemy’s proof depended on some assumptions that were hidden in the meaning of some fundamental astronomical concepts, an issue that historians of astronomy usually neglect.

After a careful examination of the Antikythera Mechanism computed tomography scans from the Antikythera Mechanism Research Project, we designed and constructed the mechanical parts that are visible on the computed tomography scans. We then reconstructed two functional models of the Antikythera Mechanism, and in this paper, we present the observations and the conclusions drawn from their use. The use of these models helped us to understand how the Mechanism worked and provided answers to questions regarding the presence and the use of some parts.

Recent scholarship on a Byzantine astronomical handbook on how to use a set of astronomical tables stemming from Islamic tradition sheds new light on a transfer of knowledge that occurred in the fourteenth century between the Ilkhanate and Byzantium. As this source was so far unpublished, the present paper gives an outline of the main textual features, then discusses the source in the framework of the cross-cultural contacts between Byzantine and non-Byzantine scholars between the Eastern Roman Empire and the Ilkhanate.